TAIYEH, Iraq -- The distress call rang out over the radio. In the midst of one of the largest current military operations in Iraq, Capt. Mike Stinchfield recognized this was, so far, his most urgent mission of the day.

A captured insurgent? A fallen comrade? Not quite. A local woman had gone into labor, and within minutes about 18 U.S. soldiers endeavored to help.

"That's a lot of men to secure a baby," said Stinchfield, 37, of Vancouver, Wash., the commander of Company H, 3rd Squadron of the Army's 2nd Stryker Cavalry Regiment. "But that's what this war is like. It's slow and boring most days, and not much happens."

Thousands of U.S. soldiers are moving against one of the largest known concentrations of fighters from the group al-Qaeda in Iraq here in a 50-square-mile pocket of Diyala province known as the Bread Basket. Company H expected resistance from 40 to 50 fighters from the Sunni insurgent group, but most of them appeared to have fled by the time the unit rolled in.

In the end, Company H didn't fight a single person. What had been envisioned as a combat mission instead became a day of emergency-service work, hours of boredom and finally tragedy, as word of fallen comrades reached them over the radio inside their Strykers, eight-wheel armored vehicles.

It was just past noon Wednesday, Day 2 of this offensive in the fertile Diyala River valley. The soldiers had been given the location of a suspected local leader of al-Qaeda in Iraq in the village of Al Ali.

But when they arrived at the home of the man, known as Abu Ayeesha, he was nowhere to be seen. His wife refused to answer questions.

The village was quiet. A teenager rode past on a bicycle carrying a lumpy sack on the back. Stinchfield stopped him.

"It's flour! Just flour!" the boy pleaded in Arabic to the military interpreter.

Stinchfield didn't respond. He looked at the boy's black coat, with the name Oscar embroidered in gold.

"Is your name Oscar?" he asked.

"No, Fouad!" the boy said.

"Well, that says your name is Oscar," Stinchfield said with a laugh. "It's an American name."

The boy looked confused, then pedaled furiously down the street.

Stinchfield returned to his Stryker, passing through a door bearing the soldiers' graffiti: "SHOW NO MERCY TO A MAN WHO SHOWS YOU NONE." They moved out and drove along a small canal that cut through several tiny villages.

Staff Sgt. David Rozmarin delivered a Catskills-in-combat shtick, with Stinchfield the straight man to the 26-year-old from Omaha.

"When are you people gonna learn it's called crick, not creek?" Rozmarin said, referring to the canal. "That's C-R-I-C-K. Crick."

"I've got a crick in my neck from all this," said Spec. Aaron Bacon, 21, of Noblesville, Ind.

Inside the Stryker, the soldiers scoured a map for areas where insurgents could hide. Then they called in mortar strikes.

A few minutes later: Thud. Thud. The mortar shells landed nearby. And then the radio came alive with news of the pregnant woman.

"This lady's about to pop!" someone yelled.

Sgt. Levar Scott, 28, of New Orleans, the company medic, rushed to the site along with more than a dozen men. Scott had assisted in only one previous delivery -- that of his son, now 5.

"A baby in combat," Scott said, shaking his head. "This is just crazy."

The woman lay on a mattress on the floor. She screamed occasionally through a piece of black cloth stuffed in her mouth.

The soldiers quickly discovered that her last delivery had been by Caesarean section, meaning she probably needed surgery and hospital care for this delivery, too. After some frantic scrambling, the soldiers arranged safe passage for the woman and her family, despite a ban on car traffic during the offensive.

"So has the war started yet?" Rozmarin asked when he returned to the Stryker.

Lunchtime. The soldiers tore open their MREs, standard military-issue food packets called Meals Ready to Eat.

"It can be very deceptive," Stinchfield said. "The enemy is out there. They just don't want to tangle with us in a direct manner."

The radio crackled with a new alarm -- a booby-trapped house, U.S. soldiers hurt. Six casualties.

Rozmarin put down his Dan Brown novel, which he said he found in a dumpster. The casualties were from another company. H Company had a platoon assigned to it.

Suddenly, another distress signal. The pregnant woman was trying to cross the river on her way to the hospital, but U.S. soldiers would not let her through. Stinchfield looked concerned.

He got on the radio to ask for help. "I know you're dealing with these casualties, but I've still got this situation with the pregnant woman."

The radio gave the next update on the soldiers' status: "Three are urgent."

Then came word that the pregnant woman had crossed U.S. lines.

As a voice on the radio announced that four casualties had been airlifted from the site of the house bomb, Stinchfield left the Stryker to talk to villagers. He walked past Pfc. Cameron Houston, 22, of Silver City, N.M., who muttered a few obscenities.

"We've been walking around doing nothing today," Houston said.

Stinchfield asked locals about al-Qaeda in Iraq. But he worried that few of them were answering honestly because they felt intimidated.

He asked Yasin Hamed Awad al-Jabour, a 68-year-old farmer in Taiyeh, about masked men seen running through the neighboring town of Himbuz as U.S. soldiers entered. Jabour said they were not part of the insurgency.

His 6-year-old grandson, Yasin Khalid, joined in. "No, no, no. We haven't seen any al-Qaeda."

"Who told you to say that?" Stinchfield asked.

The boy looked confused, and his father ushered him away.

Stinchfield sighed. "There is not black and white," he said. "That's what I learned. There's a lot of gray here in Iraq.

"In no way is this war going to be solved militarily," he added.

In a call to his platoon commanders just before 4 p.m., Stinchfield said he didn't know yet what platoon had been hit by the bombing.

"Watch your guys," he said, enunciating each syllable slowly. "Make sure they are not complacent just because it's quiet."

At 4:30 p.m., the company received an update. The pregnant woman had reached a hospital in the city of Muqdadiyah. Stinchfield said he would check on her status that night.

But soon the radio sounded with three grim initials: KIA. One of their squadron members had been killed in action. Six were seriously wounded, two others lightly.

Standing on the dusty street as the sun set, Stinchfield had trouble finding his voice. "I knew all the guys in that group," he said after a long pause.

He stopped talking and shook his head, over and over.

Back in the Stryker at about 6 p.m., Rozmarin wasn't joking anymore. He provided the updated numbers that had come over the radio. "Six KIA?" Stinchfield asked in disbelief. "Damn. Are you sure?"